PROJECT SUMMARY The overall goal of this study is to refine the tuberculosis (TB) treatment support tools (TB-TST) intervention, which links an app developed using user-centered design principles and a paper-based drug metabolite urine test strip modified for home use, to improve treatment outcomes for patients with TB, and evaluate its impact by a RCT. TB is an urgent global health threat and the world's deadliest infectious disease despite it being largely curable. Poor medication adherence to TB regimens, along with challenges in monitoring patients and returning them to treatment, are important contributing factors to poor outcomes and the development of drug resistance. Individuals with TB face multiple barriers to good treatment adherence such as medication side effects, stigma, and lack of education about the disease and its treatment. With advances in, and proliferation of, mobile technology platforms, there is substantial interest in the possible use of mobile health (mHealth) interventions to address these challenges. Of the mHealth approaches under investigation for TB adherence monitoring, drug metabolite testing has been identified as the most promising, ethical, and accurate, and the least intrusive and stigmatizing strategy compared to other mobile solutions (eg, video observation, ?smart? medication bottles, ingestible sensor), yet its potential remains largely unexplored. Additionally, mobile applications (apps) may provide personalized treatment supervision, increase patients' self-management and improve patient-provider communication by offering more advanced functionalities for patient support and monitoring. However, available TB-related apps have not focused on patients as the end- users nor have they been fully evaluated. This proposal builds on preliminary work to 1) combine input from patients and experts to iteratively design the content, features, functionalities, and interface of the treatment support app and 2) optimize a paper-based test strip for testing the presence of isoniazid drug metabolites in urine to directly monitor adherence to treatment. The existing version of the TB-TST app has the following functionalities: it offers education on TB and its treatment, communication with a care-coordinator, tracks treatment adherence (both by self-reporting and direct metabolite test strip images), self-reports treatment side-effects, and retains patient's ?diary? notes. The results from the pilot test of this version will be the starting point for this proposed study. Aims are to: 1) Refine the TB-TST intervention based on pilot study findings and apply principles of user-centered design; 2) Evaluate the impact of the TB-TST on treatment outcomes (success, default) compared to usual care; 3) Assess patient and provider perceptions of the facilitators and barriers to implementation of the TB-TST and synthesize lessons learned with stakeholders and policy makers. The primary outcome will be treatment success. Secondary outcomes will include: treatment default rates, self-reported adherence, technology use and usability. Findings have broader implications not only for TB adherence but disease management more generally and will improve our understanding of how to support patients facing challenging treatment regimens.